Would imagine it's an HOA situation.
There's a company that owns the land, and it's sole purpose is to maintain the land and common areas of the building. All the units could be individually owned, and that company exists to have a bank account that can pay for repairs/repaints. In this situation I'm describing, while the company would own the building, they have no ability to raise rents, as all the units would be owned by the tenants.